This invention relates generally to locking devices for interconnecting relatively movable concentric members and, more particularly, to a bearing assembly with a locking device for locking the bearing assembly on a rotatable shaft.
The two most common methods of locking a bearing assembly having inner and outer rings on a rotatable shaft are an eccentric locking collar design and a setscrew design. Each of these methods has drawbacks and causes rotational imbalance and down-rating of the bearing assembly load capacity.
The eccentric locking collar design holds the inner ring against the rotatable shaft at only one location and thus forces the bearing assembly to be eccentric with respect to the rotatable shaft. The amount of eccentricity is equal to the intentional clearance between the rotatable shaft and the bearing assembly. This eccentricity results in movement of the bearing assembly relative to the rotatable shaft as well as fretting of the bearing bore, some cocking of the inner ring of the bearing, and high bending stress on the inner ring. In addition, manufacture of the collar requires expensive eccentric machining.
The setscrew design also pulls the inner ring of the bearing assembly eccentric with respect to the rotatable shaft. The setscrew forces the inner ring out-of-round and puts the inner ring under tensile stress. In addition, the setscrew design may cause a burr on the rotatable shaft and may cause problems due to the presence of loose parts during the manufacturing process.
The foregoing illustrates limitations known to exist in present bearing assemblies with locking devices. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one of more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.